4 curated MTB spots in Switzerland, each with its own note and source.
Graubünden
Over 400 km of signposted bike routes, plus the flow trails on Corviglia: Marmotta at 2.2 km (easy), WM and Olympia (intermediate). Several mountain railways carry bikes, the highest up Piz Nair (3,057 m), where the alpine Val Schlattain trail starts its run down to the valley.
Sources: Engadin St. Moritz Tourismus AG, Engadin Tourismus, Engadin St. Moritz Mountains AG, skiresort.com
Graubünden
Lift-served trails from the FlemXpress and the Laax–Crap Sogn Gion cable car: Runca, 7.6 km of flow country, Never End, 7 km with 1,150 m of descent for advanced riders, and Segnes, a technical 3.7 km enduro singletrack. They may only be ridden during official lift operating hours and only when marked as open.
Sources: Flims Laax Falera, LAAX / Weisse Arena Gruppe, Flims Laax Falera Management AG
Wallis
The bike park holds nine downhill runs over 19 km, graded green, blue, red and black plus a yellow race line; descents between Les Ruinettes, Clambin and Verbier drop 700 to 880 metres. Lifts carry bikes and the season runs June to October depending on snow. The wider region adds 23 enduro trails.
Sources: Verbier 4Vallées Tourisme, Verbier – Val de Bagnes, Office du Tourisme, Verbier 4Vallées
Wallis
More than 100 km of trails between 1,400 and 3,100 m, from easy tours to hard lines for experienced riders. Around the village sit the Moos, Sunnegga, Riffelberg and Blauherd flow trails graded D1 to D4; the mountain railways carry bikes, and riding is a summer affair.
Sources: Zermatt Bergbahnen AG, Zermatt Bergbahnen AG, Zermatt Tourismus, skiresort.com, Zermatt Bergbahnen (Matterhorn Glacier Paradise)
Without a dedicated MTB note yet, listed on the country page: Champéry, Lenzerheide.